One type of vehicle suspension system which is becoming increasingly popular is the MacPherson strut suspension system. The MacPherson strut is an integral coil spring-shock absorber assembly which provides a lightweight, compact component of a vehicle suspension system. The MacPherson strut suspension system is disclosed in more detail in U.S. Pat. No. 2,624,592 to E. S. MacPherson.
One of the problems associated with MacPherson strut assemblies is related to the replacement of a worn shock absorber unit. One solution to this problem is to manufacture the MacPherson strut assembly with a construction which permits the shock absorber to be readily removed and replaced with a new shock absorber. However, such a repair procedure can be relatively time consuming, since typically the strut assembly must be removed from the vehicle.
One solution to reducing the time associated with repairing a MacPherson strut assembly is disclosed in U.S. Pat. No. 4,034,960 to K. D. Kloster. The Kloster patent discloses a pneumatic operated spring compressor which can be utilized to repair a strut assembly while the lower portion of the assembly remains attached to the vehicle. However, the economics of such a compressor can typically only be justified by repair shops which frequently repair strut suspension systems.
Smaller repair shops typically utilize a relatively inexpensive spring compressor unit of the type manufactured by Warren, Inc. of Jonesboro, Ark. This type of spring includes a pair of spaced apart U-shaped hooks which are maintained in a facing relationship by means of an elongate bolt. In operation, typically two or three of the compressor units are circumferentially spaced about the coil spring and the bolts are alternately tightened to move the U-shaped hooks towards one another, thereby compressing the spring. However, one of the problems associated with this type of spring compressor is that the U-shaped hooks do not provide a good seating relationship with the helical coil of the spring which may lead to twisting and misalignment of the spring compressor. Such twisting or misalignment may result in the dangerous condition of causing the compressor hooks to become dislodged from the spring and inflict injury upon the operator.